A plume of exhaust extends from the Mitchell Power Station, a coal-fired power plant built along the Monongahela River in New Eagle, Pennsylvania.National Journal

In the impending conflict over the Environmental Protection Agency carbon-reduction regulations President Obama will announce today, self-interest reinforces ideology.

The conservative Republican-dominated red states most ideologically resistant to federal regulation in general also tend to be the states most reliant on carbon-intensive fuels (particularly coal) for their electricity. They're also the most invested in the existing fossil-fuel economy.

By contrast, the blue Democratic-leaning states most ideologically sympathetic to Obama's efforts against climate change also tend to be less reliant on coal for their electricity and less integrated into the fossil-fuel economy.

That stark contrast is especially significant because the EPA regulation does not impose specific emission levels on each power plant but instead establishes required levels for total carbon reductions related to electricity generation from each state. The rule provides each state considerable flexibility to meet its target, with options for improving energy efficiency to increasing reliance on renewable power sources. But, even so, the regulation is expected to drive a steady reduction in reliance on coal-fired power plants.

As the maps below show, red and blue states begin this process in very different positions relative to carbon emissions. The first map ranks the states based on how much carbon they emit per each megawatt of electricity they generate, according to the figures the EPA issued when it released the proposed rule last year. Since coal emits much more carbon per unit of electricity generated than other fuels (such as natural gas, much less solar or wind), the states that rely most on coal for their power top the list for electricity-related carbon emissions.

Electricity map (National Journal)

That list tilts strongly toward red states.

All 10 of the states that emit the most carbon per megawatt-hour of electricity generated voted for Mitt Romney over Obama in 2012, including (in order) Montana, Kentucky, Wyoming, West Virginia, Nebraska, North Dakota, Missouri, Kansas, Indiana, and Tennessee. In all, Romney carried 14 of the 20 states that emit the most carbon per megawatt-hour.

Obama by contrast, carried 15 of the 20 states that emit the least carbon per megawatt hour of electricity generated, and nine of the 10 states with the absolute lowest emissions. Idaho, a red state, ranked lowest in the EPA calculation, but it was followed, in order, by Maine, California, Oregon, Washington, Connecticut, New Hampshire, Rhode Island, Massachusetts, and New Jersey. They have all voted Democratic in at least the past six consecutive presidential elections.

As the second map shows, the same pattern holds on a broader measure that ranks the states based on their total energy-related carbon emissions per capita as of 2011 (the latest year for which figures are available). All 10 of the states that emit the most energy-related carbon per person preferred Romney over Obama in 2012, including, in order, Wyoming, North Dakota, Alaska, West Virginia, Louisiana, Kentucky, Indiana, Montana, Oklahoma, and Nebraska, according to federal Energy Information Administration figures. In all, Romney carried 17 of the 20 states that emit the most energy-related carbon per capita.

Janie Boschma

Again, the symmetry is striking. Obama carried nine of the 10 states that emit the least energy-related carbon per capita (with Idaho again as the only exception) and 17 of the lowest 20. (The middle 10 states split with six for Obama and four for Romney.)

Put another way, exactly three-fourths of the 24 states that voted for Romney in 2012 emitted more carbon per person than the national average in energy usage, while slightly more than three-fourths of the 26 states that voted for Obama emitted less. Of the 18 states that have voted Democratic in at least the past six consecutive elections — what I've termed the "blue wall" — all but Pennsylvania and Illinois emit less carbon per capita in energy use than the national average.

As I noted in an analysis when the EPA released the proposed regulations last year, this contrast reflects a deeper divergence in the economies of red and blue states: "Many red states are heavily invested in the fossil-fuel economy, either as producers of oil, natural gas, and coal, or as large consumers of low-cost, coal-powered electricity (partly because several are manufacturing centers). The blue states, with only a few exceptions, produce little fossil fuel, rely less on coal for electricity, and generate less carbon (partly because many have moved further toward a postindustrial, white-collar economy)."

In a recent interview, Mark Tercek, president and CEO of the Nature Conservancy, an environmental group that has devoted intensive effort to building coalitions with conservatives, acknowledged that the red states' greater reliance on carbon-intensive electricity complicates the challenge of building a political coalition behind confronting climate change. "It would be silly to pretend that's easy to address," he said during an interview at the Aspen Ideas Festival. "That's why I'm cautious about when we'll get this comprehensive legislation. "... [But] just like gay marriage, public sentiment seems to be changing, so we have that going for us. We have economics going for us, which is really a powerful motivator for conservatives and liberals. We have, sadly, continued extreme weather events that get people's attention."

When the EPA issued its proposed regulations last year, many environmentalists and some blue-state governors complained that it conceded too much to these political and economic dynamics by generally asking for greater percentage carbon reductions from blue states (with lower emission levels today) than from the red states that currently emit the most.

The proposed rules, for instance, asked for carbon reductions of just 11 percent from North Dakota and 18 percent from Kentucky but 48 percent from Oregon and 44 percent from New York. Analysts will be combing through the final rules to see how, if at all, the EPA has adjusted those mandates.

Notwithstanding those concessions, several Republican governors have already signaled that they do not intend to submit plans for reducing their state's carbon emissions to the EPA, as the rule requires. Others have already telegraphed their intention to sue to block the regulations. Like the expansion of Medicaid under Obama's Affordable Care Act, the president's rule to combat climate change seems guaranteed to open another fissure between red and blue America.

Janie Boschma contributed to this article

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